10 Mr. W. C. Williamson on the Recent 



If then the Lagena be true Foraminifera, the next question is, 

 what relationship do they bear to the other organisms of the same 

 group ? I apprehend that most if not all the Foraminifera, like 

 other Bryozoa, however large and complicated they ultimately 

 become, commence their existence as single isolated cells, upon 

 or around which others are subsequently built ; some linearly, as 

 in Nodosaria and Glandulina ; others spirally, as in Rotalina, 

 Truncatulina, Polystomella, &c. ; whilst others again present va- 

 rious modifications of these two types, as Marginulina, Crist el- 

 laria, Spirulina, Quinqueloculina, &c. 



The most simple of the above structures belong to the genera 

 Nodosaria and Dentalina, and consist only of a few smooth cells 

 piled one upon another with connecting necks. Now a Lagena, 

 in its perfect and matured form, must closely resemble the iso- 

 lated germinal cell of one of these, exhibiting a phenomenon, of 

 which analogues occur in every department of the organic world. 

 It becomes then the most simple and primitive type of the Fora- 

 minifera; bearing in this respect the same relationship to the 

 more complex forms that the globule of the Torula or Yeast-plant 

 does to Nostoc, Anabaina, &c. amongst the Confervse, and that 

 Eunotia does to Fragillaria and young states of the Diatomee 

 amongst the Diatomacese. It is another instance of the grada- 

 tion, so admirably distinguished by Mr. Lyell and Mr. Miller *, 

 from the erroneous and recently abused doctrines of development 

 and progression. 



At the same time that the analogy of form and external con- 

 tour thus links the Lagena with Nodosaria and Dentalina, the 

 structure of the cell already described appears to indicate a con- 

 nexion between them and the genus Escliara and its allies. This 

 affinity shows that there are great difficulties in the way of re- 

 ceiving any of the existing linear arrangements of these objects, 

 and that a new classification will be required, based on a much 

 more extended series of observations upon the physiological cha- 

 racters of all the genera than we as yet possess. This subject 

 presents a wide and interesting field of inquiry for those who 

 reside on the sea-coast and have access to these objects in a 

 living state. 



The only general fact which remains to be noticed respecting 

 the Lagena, is the extraordinary capacity for variation which they 

 exhibit in different states and ages. Extreme forms which appear 

 to be very distinct from one another may be connected together 

 by specimens of an intermediate aspect to an extent only to be 

 believed by those who examine a large series of specimens side 

 by side. I am well aware that the synthetical plan which I have 



* ' Old Red Sandstone,' by H. Miller, Esq., p. 52. 



